Part of databind#3072: Make @JacksonInject not fail when there's no corresponding value

src/main/java/com/fasterxml/jackson/databind/DeserializationContext.java

@@ -6,6 +6,7 @@
 import java.util.*;
 import java.util.concurrent.atomic.AtomicReference;
 
+import com.fasterxml.jackson.annotation.JacksonInject;
 import com.fasterxml.jackson.annotation.JsonFormat;
 import com.fasterxml.jackson.annotation.ObjectIdGenerator;
 import com.fasterxml.jackson.annotation.ObjectIdResolver;
@@ -38,6 +39,8 @@
 import com.fasterxml.jackson.databind.type.TypeFactory;
 import com.fasterxml.jackson.databind.util.*;
 
+import static com.fasterxml.jackson.databind.DeserializationFeature.FAIL_ON_UNKNOWN_INJECT_VALUE;
+
 /**
  * Context for the process of deserialization a single root-level value.
  * Used to allow passing in configuration settings and reusable temporary
@@ -463,15 +466,32 @@ public final boolean hasSomeOfFeatures(int featureMask) {
      */
     public final JsonParser getParser() { return _parser; }
 
+    /**
+     * @since 2.20
+     */
     public final Object findInjectableValue(Object valueId,
-            BeanProperty forProperty, Object beanInstance)
+            BeanProperty forProperty, Object beanInstance, Boolean optional)
         throws JsonMappingException
     {
         if (_injectableValues == null) {
+            if (Boolean.TRUE.equals(optional) || !isEnabled(FAIL_ON_UNKNOWN_INJECT_VALUE)) {
+                return JacksonInject.Value.empty();
+            }
             return reportBadDefinition(ClassUtil.classOf(valueId), String.format(
 "No 'injectableValues' configured, cannot inject value with id [%s]", valueId));
         }
-        return _injectableValues.findInjectableValue(valueId, this, forProperty, beanInstance);
+        return _injectableValues.findInjectableValue(valueId, this, forProperty, beanInstance, optional);
+    }
+
+    /**
+     * @deprecated in 2.20
+     */
+    @Deprecated // since 2.20
+    public final Object findInjectableValue(Object valueId,
+                                            BeanProperty forProperty, Object beanInstance)
+            throws JsonMappingException
+    {
+        return this.findInjectableValue(valueId, forProperty, beanInstance, null);
     }
 
     /**

src/main/java/com/fasterxml/jackson/databind/DeserializationFeature.java

@@ -1,5 +1,6 @@
 package com.fasterxml.jackson.databind;
 
+import com.fasterxml.jackson.annotation.JacksonInject;
 import com.fasterxml.jackson.databind.cfg.ConfigFeature;
 import com.fasterxml.jackson.databind.exc.InvalidNullException;
 
@@ -266,7 +267,7 @@ public enum DeserializationFeature implements ConfigFeature
      * white space or comments, if supported by data format).
      *<p>
      * Feature is disabled by default (so that no check is made for possible trailing
-     * token(s)) for backwards compatibility reasons.
+     * token(s)) for backwards-compatibility reasons.
      *
      * @since 2.9
      */
@@ -336,6 +337,20 @@ public enum DeserializationFeature implements ConfigFeature
      */
     FAIL_ON_UNEXPECTED_VIEW_PROPERTIES(false),
 
+    /**
+     * Feature that determines the handling of injected properties during deserialization.
+     *<p>
+     * When enabled, if an injected property is not encountered during deserialization,
+     * an exception is thrown.
+     * When disabled, no exception is thrown.
+     * @see JacksonInject#optional() to configure the same behavior on single properties,
+     *<p>
+     * In Jackson 2.x, this feature is enabled by default to maintain backwards-compatibility.
+     *
+     * @since 2.20
+     */
+    FAIL_ON_UNKNOWN_INJECT_VALUE(true),
+
     /*
     /******************************************************
     /* Structural conversion features

src/main/java/com/fasterxml/jackson/databind/InjectableValues.java

@@ -4,6 +4,8 @@
 
 import com.fasterxml.jackson.databind.util.ClassUtil;
 
+import static com.fasterxml.jackson.databind.DeserializationFeature.FAIL_ON_UNKNOWN_INJECT_VALUE;
+
 /**
  * Abstract class that defines API for objects that provide value to
  * "inject" during deserialization. An instance of this object
@@ -23,7 +25,16 @@ public abstract class InjectableValues
      * @param forProperty Bean property in which value is to be injected
      * @param beanInstance Bean instance that contains property to inject,
      *    if available; null if bean has not yet been constructed.
+     * @param optional Flag used for configuring the behavior when the value
+     *    to inject is not found
+     */
+    public abstract Object findInjectableValue(Object valueId, DeserializationContext ctxt,
+            BeanProperty forProperty, Object beanInstance, Boolean optional) throws JsonMappingException;
+
+    /**
+     * @deprecated in 2.20
      */
+    @Deprecated // since 2.20
     public abstract Object findInjectableValue(Object valueId, DeserializationContext ctxt,
             BeanProperty forProperty, Object beanInstance) throws JsonMappingException;
 
@@ -63,9 +74,12 @@ public Std addValue(Class<?> classKey, Object value) {
             return this;
         }
 
+        /**
+         * @since 2.20
+         */
         @Override
         public Object findInjectableValue(Object valueId, DeserializationContext ctxt,
-                BeanProperty forProperty, Object beanInstance) throws JsonMappingException
+                BeanProperty forProperty, Object beanInstance, Boolean optional) throws JsonMappingException
         {
             if (!(valueId instanceof String)) {
                 ctxt.reportBadDefinition(ClassUtil.classOf(valueId),
@@ -75,10 +89,24 @@ public Object findInjectableValue(Object valueId, DeserializationContext ctxt,
             }
             String key = (String) valueId;
             Object ob = _values.get(key);
-            if (ob == null && !_values.containsKey(key)) {
-                throw new IllegalArgumentException("No injectable value with id '"+key+"' found (for property '"+forProperty.getName()+"')");
+            if (ob == null && !_values.containsKey(key)
+                    && !Boolean.TRUE.equals(optional)
+                    && ctxt.isEnabled(FAIL_ON_UNKNOWN_INJECT_VALUE)) {
+                throw new IllegalArgumentException("No injectable value with id '" + key + "' " +
+                        "found (for property '" + forProperty.getName() + "')");
             }
             return ob;
         }
+
+        /**
+         * @deprecated in 2.20
+         */
+        @Override
+        @Deprecated // since 2.20
+        public Object findInjectableValue(Object valueId, DeserializationContext ctxt,
+                                          BeanProperty forProperty, Object beanInstance) throws JsonMappingException
+        {
+            return this.findInjectableValue(valueId, ctxt, forProperty, beanInstance, null);
+        }
     }
 }

src/main/java/com/fasterxml/jackson/databind/deser/BeanDeserializerBuilder.java

@@ -239,9 +239,12 @@ public void  addBackReferenceProperty(String referenceName, SettableBeanProperty
         */
     }
 
+    /**
+     * @since 2.20
+     */
     public void addInjectable(PropertyName propName, JavaType propType,
             Annotations contextAnnotations, AnnotatedMember member,
-            Object valueId)
+            Object valueId, Boolean optional)
         throws JsonMappingException
     {
         if (_injectables == null) {
@@ -254,7 +257,19 @@ public void addInjectable(PropertyName propName, JavaType propType,
                 _handleBadAccess(e);
             }
         }
-        _injectables.add(new ValueInjector(propName, propType, member, valueId));
+        _injectables.add(new ValueInjector(propName, propType, member, valueId, optional));
+    }
+
+    /**
+     * @deprecated in 2.20
+     */
+    @Deprecated // since 2.20
+    public void addInjectable(PropertyName propName, JavaType propType,
+                              Annotations contextAnnotations, AnnotatedMember member,
+                              Object valueId)
+            throws JsonMappingException
+    {
+        this.addInjectable(propName, propType, contextAnnotations, member, valueId, null);
     }
 
     /**

src/main/java/com/fasterxml/jackson/databind/deser/BeanDeserializerFactory.java

@@ -812,11 +812,16 @@ protected void addInjectables(DeserializationContext ctxt,
     {
         Map<Object, AnnotatedMember> raw = beanDesc.findInjectables();
         if (raw != null) {
+            final AnnotationIntrospector introspector = ctxt.getAnnotationIntrospector();
+
             for (Map.Entry<Object, AnnotatedMember> entry : raw.entrySet()) {
                 AnnotatedMember m = entry.getValue();
+                final JacksonInject.Value injectableValue = introspector.findInjectableValue(m);
+                final Boolean optional = injectableValue == null ? null : injectableValue.getOptional();
+
                 builder.addInjectable(PropertyName.construct(m.getName()),
                         m.getType(),
-                        beanDesc.getClassAnnotations(), m, entry.getKey());
+                        beanDesc.getClassAnnotations(), m, entry.getKey(), optional);
             }
         }
     }

src/main/java/com/fasterxml/jackson/databind/deser/CreatorProperty.java

@@ -103,7 +103,7 @@ public CreatorProperty(PropertyName name, JavaType type, PropertyName wrapperNam
     {
         this(name, type, wrapperName, typeDeser, contextAnnotations, param, index,
                 (injectableValueId == null) ? null
-                        : JacksonInject.Value.construct(injectableValueId, null),
+                        : JacksonInject.Value.construct(injectableValueId, null, null),
                 metadata);
     }
 

src/main/java/com/fasterxml/jackson/databind/deser/impl/PropertyValueBuffer.java

@@ -269,7 +269,7 @@ protected Object _findMissing(SettableBeanProperty prop) throws JsonMappingExcep
         Object injectableValueId = prop.getInjectableValueId();
         if (injectableValueId != null) {
             return _context.findInjectableValue(prop.getInjectableValueId(),
-                    prop, null);
+                    prop, null, null);
         }
         // Second: required?
         if (prop.isRequired()) {

src/main/java/com/fasterxml/jackson/databind/deser/impl/ValueInjector.java

@@ -2,6 +2,7 @@
 
 import java.io.IOException;
 
+import com.fasterxml.jackson.annotation.JacksonInject;
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.introspect.AnnotatedMember;
 
@@ -21,11 +22,30 @@ public class ValueInjector
      */
     protected final Object _valueId;
 
+    /**
+     * Flag used for configuring the behavior when the value to inject is not found
+     */
+    protected final Boolean _optional;
+
+    /**
+     * @since 2.20
+     */
     public ValueInjector(PropertyName propName, JavaType type,
-            AnnotatedMember mutator, Object valueId)
+            AnnotatedMember mutator, Object valueId, Boolean optional)
     {
         super(propName, type, null, mutator, PropertyMetadata.STD_OPTIONAL);
         _valueId = valueId;
+        _optional = optional;
+    }
+
+    /**
+     * @deprecated in 2.20 (remove from 3.0)
+     */
+    @Deprecated // since 2.20
+    public ValueInjector(PropertyName propName, JavaType type,
+            AnnotatedMember mutator, Object valueId)
+    {
+        this(propName, type, mutator, valueId, null);
     }
 
     /**
@@ -42,12 +62,15 @@ public ValueInjector(PropertyName propName, JavaType type,
     public Object findValue(DeserializationContext context, Object beanInstance)
         throws JsonMappingException
     {
-        return context.findInjectableValue(_valueId, this, beanInstance);
+        return context.findInjectableValue(_valueId, this, beanInstance, _optional);
     }
 
     public void inject(DeserializationContext context, Object beanInstance)
         throws IOException
     {
-        _member.setValue(beanInstance, findValue(context, beanInstance));
+        final Object value = findValue(context, beanInstance);
+        if (!JacksonInject.Value.empty().equals(value)) {
+            _member.setValue(beanInstance, value);
+        }
     }
 }

src/main/java/com/fasterxml/jackson/databind/deser/std/StdValueInstantiator.java

@@ -673,7 +673,7 @@ private Object _createUsingDelegate(AnnotatedWithParams delegateCreator,
                 if (prop == null) { // delegate
                     args[i] = delegate;
                 } else { // nope, injectable:
-                    args[i] = ctxt.findInjectableValue(prop.getInjectableValueId(), prop, null);
+                    args[i] = ctxt.findInjectableValue(prop.getInjectableValueId(), prop, null, null);
                 }
             }
             // and then try calling with full set of arguments

src/test/java/com/fasterxml/jackson/databind/introspect/IntrospectorPairTest.java

@@ -697,14 +697,19 @@ public JacksonInject.Value findInjectableValue(AnnotatedMember m) {
 
     static class TestInjector extends InjectableValues {
         @Override
-        public Object findInjectableValue(Object valueId, DeserializationContext ctxt, BeanProperty forProperty, Object beanInstance) {
+        public Object findInjectableValue(Object valueId, DeserializationContext ctxt, BeanProperty forProperty, Object beanInstance, Boolean optional) {
             if (valueId == "jjj") {
                 UnreadableBean bean = new UnreadableBean();
                 bean.setValue(1);
                 return bean;
             }
             return null;
         }
+
+        @Override
+        public Object findInjectableValue(Object valueId, DeserializationContext ctxt, BeanProperty forProperty, Object beanInstance) {
+            return this.findInjectableValue(valueId, ctxt, forProperty, beanInstance, null);
+        }
     }
 
     enum SimpleEnum { ONE, TWO }